Kenmore Coldspot Not Defrosting Properly

[tron]

Model Number

106.8670380

Hello,

I have an old Sears/Kenmore Coldspot refrigerator that serves primarily as a beer fridge and lives in my garage. Lately it has not been cooling properly. I've done some troubleshooting and found a few things:

• Thick frost is building up in the back of the freezer on the evaporator fins.
• After manually defrosting (with a hair dryer) and melting all the frost, everything functions properly for a while but the frost returns within about a week and the temperature rises.
• When I manually turn the defrost timer to defrost mode using a screwdriver, the heater seems to kick on for about 30 seconds (I can hear some hissing and popping as if it's heating up) but it doesn't fully defrost.
• If I turn the defrost timer to defrost mode and let it go, it eventually goes back into cooling mode (the fan and compressor both turn on).

Based on what I've been reading, this seems as if it's most likely a problem with the defrost timer, the thermostat, or the actual heater. Can anyone help me figure out the exact cause and whether or not it's worth fixing? Thanks in advance!

-Tron

 

[Jake]

Hi Tron,

When you say the defrost heater comes on for 30 seconds, what does it do after that? Is the entire evaporator coil frosted up to where you can't see the coils?

You see where the defrost thermostat is mounted? Is there always frost covering it or frost always covering the coil it mounts to while the defrost heater is on?

Because it should stay on much longer than 30 seconds if the defrost thermostat is covered in frost or there is frost on the coil it mounts to.

The defrost timer controls how long it stays in the defrost cycle, and that varies between 25-40 minutes.

Here's your OEM defrost thermostat: Defrost Thermostat WP4387499 Open at 50'F close at 25'F.

So yours is bad if the defrost heater is only staying on 30 seconds with the frost on it still.

Jake